The present invention relates to a method for making seams especially preferred for use in disposable, pant-like articles having at least one fixed side comprising a flangeless seam. Examples of such disposable articles include training pants, pull-on diapers or adult incontinence articles, disposable underwear for children (e.g., toddlers) or adults, and disposable panties which may be used with catamenial devices such as tampons or sanitary napkins.
Infants and other incontinent individuals wear disposable absorbent articles to receive and contain urine and other bodily exudates. Absorbent articles having fixed sides have been popular for use in adult incontinence articles and children""s toilet-training articles because it is desirable to have an absorbent article which is very garment-like in appearance and feel. (As used herein, xe2x80x9carticles having fixed sidesxe2x80x9d refer to disposable articles such as adult incontinence briefs and training pants which are provided to the consumer in a pant-like configuration. Thus, the articles generally have the front and rear portions joined together to form a waist hoop and leg holes. This is unlike conventional diapers which are provided to the consumer with the front and rear portions unjoined.) For adults, the garment-like appearance and feel can help reduce any embarrassment associated with the use of incontinence articles. For children, especially in their toilet training stage, the garment-like feel and appearance can help the child distinguish the article, such as training pants, from a diaper and can help the child adjust to cloth undergarments.
One example of a commercially available disposable training pant is disclosed in U.S. Pat. No. 5,246,433 entitled xe2x80x9cElasticized Disposable Training Pant and Method of Making the Samexe2x80x9d, issued to Hasse et al. on Sep. 21, 1993. Although this training pant has been a commercial success, it still suffers because it includes seams joining the front and rear portions which are not garment-like in appearance. Such seams are often constructed by positioning the lateral edges of the front and rear portions of the article in a face-to-face relationship with one another and then gluing, sewing, heat sealing, pressure bonding or ultrasonically sealing the edges to form flanges or fin seams. The flanges or fins are unsightly if located on the outwardly facing surface of the article or irritating to the wearer if located on the inward surface. Thus, attempts have been made to reduce the outwardly or inwardly extending portions of the flanges of fin seams. However, in so doing the process for making the seams generally becomes more complex and costly and may reduce the strength of the bond.
Thus, it would be advantageous to be able to provide a flangeless seam that can be constructed economically. It would also be advantageous to provide a flangeless seam that could be produces on machinery that is very similar to that already in place. Further, it would be advantageous to reduce the amount of material that is needed to produce an aesthetically pleasing seam that is strong enough to hold together the front and rear portions of a disposable absorbent article.
The method of then present invention provides a solution to the problems of the prior art by providing an inexpensive means to manufacture seams. The method includes the following steps: A first member of a disposable article is provided. An electromagnetic field responsive member is provided on the first member. A second member of the disposable article is provided juxtaposed at least a portion of the first member to form a laminate including the first member and the second member. An electromagnetic field is applied across at least a portion of the laminate to heat the electromagnetic field responsive member to join at least a portion of the first member and at least a portion of the second member.
In a particularly preferred embodiment to manufacture a flangeless seam, the method includes the following steps: A first member of a disposable article is provided. The first member is folded about the electromagnetic field responsive member providing opposing first proximal and first distal portions of the first member, the electromagnetic field responsive member being disposed at least partially between the opposing first proximal and first distal portions. A second member of the disposable article is provided in a folded configuration juxtaposed at least a portion of the first member to form a laminate including the first member and the second member. An electromagnetic field is applied across at least a portion of the laminate to heat the electromagnetic field responsive member to join at least a portion of the first member and at least a portion of the second member. The resulting seam can be opened to provide the article with a flangeless seam.